Drilling motors utilize fluid energy converted to mechanical energy to provide shaft rotation to a drill string or drill bit. Because the drilling motor is a highly loaded section of a drilling tool, it is prone to critical damage during motor transmission failure. Failure of the motor transmission may result in critical damage to the motor transmission assembly, including the separation of components from the transmission assembly. Where such separation occurs, these components may be lost downhole. The lost components dropped downhole can prevent further progression in drilling and can cause significant delays.
A procedure commonly known as “fishing” is sometimes used to retrieve the lost components, but this procedure is costly and time-consuming, and in certain instances may be ineffective. In some instances, the loss of components downhole can result in abandonment of a drilling project.